Hinge mechanism for a fluid filled lens assembly

ABSTRACT

In an embodiment, a hinge for a fluid-filled lens assembly includes a base having a first end configured to connect to a temple arm of the lens assembly and a second end configured to connect to a frame of the lens assembly, wherein the base includes a gap that is shaped to allow for tubing to pass from the first end to the second end of the base. In an embodiment, the first end of the base includes a cammed surface configured to engage a surface of the temple arm. In an embodiment, the first and second ends of the base are configured to flex around a rotation axis of the hinge.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of U.S. application Ser.No. 13/739,780, filed Jan. 11, 2013, which is a continuation applicationof U.S. application Ser. No. 12/904,769 filed Oct. 14, 2010, whichclaims priority to U.S. Provisional Patent Application No. 61/251,819,filed Oct. 15, 2009, all of which are incorporated herein by referencein their entirety.

BACKGROUND

1. Field

Embodiments of the present invention relate to fluid-filled leases andin particular to variable fluid-filled lenses.

2. Background Art

Basic fluid lenses have been known since about 1958, as described U.S.Pat. No. 2,836,101, incorporated herein by reference in its entirety.More recent examples may be found in “Dynamically Reconfigurahle FluidCore Fluid Cladding Lens in a Microfluidie Channel” by Tang et al., LabChip, 2008, vol. 8, p. 395, and in WIPO publication WO2008/063442, eachof which is incorporated herein by reference in its entirety. Theseapplications of fluid lenses are directed towards photonics, digitalphone and camera technology and microelectronics.

Fluid lenses have also been proposed for ophthalmic applications (see,e.g., U.S. Pat. No. 7,085,065, which is incorporated herein by referencein it entirety). In all cases, the advantages of fluid lenses, such as awide dynamic range, ability to provide adaptive correction, robustness,and low cost have to be balanced against limitations in aperture size,possibility of leakage, and consistency in performance. The '065 patent,example, has disclosed several improvements and embodiments directedtowards effective containment of the fluid in the fluid lens to be usedin ophthalmic applications, although not limited to them (see, e.g.,U.S. Pat. No. 6,618,208, which is incorporated by reference in itsentirety). Power adjustment in fluid lenses has been effected byinjecting additional fluid into a lens cavity, by electrowetting,application of ultrasonic impulse, and by utilizing swelling forces in across-linked polymer upon introduction of a swelling agent such aswater.

BRIEF SUMMARY

In an embodiment, a hinge for a fluid-filled lens assembly includes abase having a first end configured to connect to a temple arm of thelens assembly and a second end configured to connect to a frame of thelens assembly, wherein the base includes a gap that is shaped to allowfor tubing to pass from the first end to the second end of the base. Inan embodiment, the first end of the base includes a cammed surfaceconfigured to engage a surface of the temple arm. In an embodiment, thefirst and second ends of the base are configured to flex around arotation axis of the hinge.

In another embodiment, a fluid-filled lens assembly comprises: a templearm; a reservoir disposed within the housing; frame; a fluid-filled lensdisposed within the frame; tubing connecting the reservoir to thefluid-fined lens; and a hinge attached to the temple arm and to theframe. The hinge tides a base having a gap that is shaped to allow fortubing to pass from a first end to a second end of base.

Further embodiments, features, and advantages of the present invention,as well as the structure and operation of the various embodiments of thepresent invention, are described in detail below with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS/FIGURES

The accompanying drawings, which are incorporated herein and form a partof the specification, illustrate the present invention and, togetherwith the description, further serve to explain the principles of theinvention and to enable a person skilled in the pertinent art to makeand use the invention.

FIG. 1 illustrates a perspective view of an embodiment of a caliperactuator assembly.

FIG. 2 illustrates an exploded perspective view of an embodiment of acaliper actuator assembly,

FIG. 3 illustrates a first set of steps for assembling an embodiment ofa temple chassis subassembly.

FIG. 4 illustrates a second set of steps for assembling an embodiment ofa temple chassis subassembly.

FIG. 5 illustrates a set of steps for assembling a temple subassembly,according to an embodiment.

FIG. 6 illustrates a first set of steps for assembling a frame assembly,according to an embodiment.

FIG. 7 illustrates a second set of steps for assembling a frameassembly, according to an embodiment.

FIG. 8 illustrates a completed frame assembly, according to anembodiment.

FIG. 9 illustrates a spring connected to a temple arm, according to anembodiment.

FIG. 10 illustrates a spring connected to a temple arm, according to anembodiment.

FIG. 11 shows a hinge, according to an embodiment.

FIG. 12 shows a hinge, according to an embodiment.

FIG. 13 shows a view of a leaf spring hinge embodiment,

FIG. 14 shows further views of a leaf spring hinge embodiment.

FIG. 15 shows further views of a leaf spring hinge embodiment.

FIG. 16 shows a further view of a leaf spring hinge embodiment.

FIG. 17 illustrates an exploded view of a leaf spring hinge embodiment.

FIG. 18 shows a view of a sheet metal spring hinge, according to anembodiment.

FIG. 19 shows further views of a sheet metal spring hinge, according toan embodiment.

FIG. 20 shows further views of a sheet metal spring hinge, according toan embodiment.

FIG. 21 shows a further vie sheet metal spring hinge, according to anembodiment.

FIG. 22 illustrates an exploded view of a sheet metal spring hingeembodiment.

FIG. 23 shows multiple views of assembled pair of eyeglasses, accordingto an embodiment.

DETAILED DESCRIPTION

Although specific configurations and arrangements are discussed, itshould be understood that this is done liar illustrative purposes only.A person skilled in the pertinent art will recognize that otherconfigurations and arrangements can be used without departing from thespirit and scope of the present invention. It will be apparent to aperson skilled in the pertinent art that this invention can also beemployed in a variety of other applications.

It is noted that references in the specification to “one embodiment,”“an embodiment,” “an example embodiment,” etc., indicate that theembodiment described can include a particular feature, structure, orcharacteristic, but every embodiment may not necessarily include theparticular feature, structure, or characteristic. Moreover, such phrasesdo not necessarily refer to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with an embodiment, it would be within the knowledge of oneskilled in the art to affect such feature, structure or characteristicin connection with other embodiments whether or not explicitlydescribed.

Fluid lenses have important advantages over conventional means of visioncorrection, such as rigid lenses and contact lenses. First, fluid lensesare easily adjustable. Thus an individual who requires an additionalpositive power correction to view near objects can be fitted with afluid lens of base power matching the distance prescription. The usercan then adjust the fluid lens to obtain additional positive powercorrection as needed to view objects at intermediate and otherdistances.

Second fluid lenses can be adjusted continuously over a desired powerrange by the wearer. As a result, the wearer can adjust the power toprecisely match the refractive error for a particular object distance ina particular light environment. Thus, fluid lenses allow adjustment ofpower to co compensate for alteration of the natural depth of focus ofthe eye that depends on the wearer's pupil size, which is in turndependent on the ambient light level.

Third, although 20/20 vision, which corresponds to an image resolutionof 1 minute of arc ( 1/60 degree) is generally acknowledged to representan acceptable quality of vision, the human retina is capable of finerimage resolution. It is known that a healthy human retina is capable ofresolving 20 seconds of arc ( 1/300 degree). Corrective eyeglassesdesigned to enable a patient to achieve this superior level of visionhave a resolution of about 0.10D or better. This resolution can beachieved with continuously adjustable fluid lens elements.

In an embodiment of a fluid filled lens in a pair of eyeglasses, theoptical power of the fluid filled lens may be adjusted by moving anactuator attached to a reservoir located in a temple arm of the eyeglassframe. The reservoir is attached to the fluid filled lens via aconnecting tube. Moving the actuator a first way compresses thereservoir and pushes fluid into the fluid lens. Moving the actuator asecond way allows the reservoir to expand and pull fluid from the fluidlens. The compression and expansion of the reservoir changes the opticalpower of the fluid filled lens. In an embodiment, one or more fluidlenses may be provided, each with its own actuation system, so that alens for each eye may be adjusted independently. This feature allowwearers, such as anisometropic patients, to correct any refractive errorin each eye separately, so as to achieve appropriate correction in botheves, which can result in better binocular vision and binocularsummation. Further description and additional embodiments of thereservoir are described in U.S. application Ser. No. 12/904,736.

In such fluid filled lens designs, the fluid must pass from thereservoir located in the temple arm of the eyeglasses through a hingelocated at the juncture between the temple arm and the lens framelocated on the front of the eyeglasses. Because the hinge is subject torepeated bending, the connecting tube may prematurely fail if made of aweak material. Further, if the connecting tube is bent beyond a certainlevel, the fluid pressure in the lens may be affected. Accordingly, afluid filled lens assembly according to an embodiment of the presentinvention provides ample space within the temple and end piece for theconnecting tube to bend without kinking. In addition, according to anembodiment, the entire hinge mechanism may be located within the volumeof the temple arm and frame.

FIG. 1 illustrates a perspective view of a caliper actuator assembly100, according to an embodiment of the present invention. Caliperactuator assembly 100 includes temple cover 110, which includes a hollowouter portion and a hollow inner portion formed together to encloseadditional pieces of caliper actuator assembly 100. Distal end 160 oftemple cover 110 is shaped to fit over a wearer's ear. Caliper actuatorassembly 100 further includes temple chassis 120, wheel 130, and slider140. In an embodiment, wheel 130 and slider 140 are longitudinallyslidably disposed within temple chassis 120. Caliper actuator assembly100 operates to compress reservoir 150 and transfer fluid betweenreservoir 150 and a fluid lens (not shown). The compressing force may beapplied in various ways, such as for example, by rotating wheel 130 orby translating the wheel along a slot. Additional methods of applyingcompressing force are also described herein. The compression ofreservoir 150 may be effected either by compressing reservoir 150 in avertical or horizontal direction against a ceiling or inner wall oftemple chassis 120, as described in detail below.

FIG. 2 illustrates an exploded perspective view of an embodiment ofcaliper actuator assembly 100. In an embodiment, slider subassembly 295(described below with respect to FIGS. 3-4) is configured to translatealong one or more of temple cover 110 and temple chassis 120 in order tocompress reservoir 150. In operation, a user rotates wheel 130, whichmoves slider block 255, which in turn compresses a relatively stiffmetal plate, such as compression arm 270, that is in contact with afirst side surface 265 of reservoir 150. A second side surface (notshown) of reservoir 150 is placed against inner wall 285 of templechassis 120, a portion of temple cover 110, or any other suitablesurface. Slider 140 presses against compression arm 270, whichcompresses reservoir 150 in a controllable manner. In an embodiment, thelength of the lateral movement of wheel 130 is proportional to themagnitude of compression of the compression arm, and is proportional tothe magnitude of compression of the reservoir. Further description andadditional embodiments of the actuator are described in U.S. applicationSer. No. 12/904,720.

In an embodiment, wheel 130 has a knurled edge in order to providesecure contact with the finger of the user as well more precise controlover the translation of wheel 130.

Lens module 200 is connected via outlet port 245 to a connecting tube(not shown), which is connected to reservoir 150. Lens module 200 mayfurther include a flexible back surface provided by, for example, aflexible membrane (not shown) stretched flat over the edge of rigidoptical lens. To change the optical power of fluid filled lens module200, the membrane may be inflated through the addition of a fluid incommunication with reservoir 150.

The connecting tube delivers fluid from lens module 200 to reservoir 150and vice versa. The connecting tube is designed to be relativelyimpermeable to the fluid contained therein. In an embodiment, theconnecting tube is configured to allow a minimum flow rate at all timesin order to ensure a minimum speed of response to the user moving wheel130 in order to change the optical power of fluid filled lens module200. The connecting tube is connected at one end to outlet port 245 oflens module 200 and at the other end to reservoir 150. In an embodiment,the overall assembly including the lens module 200, the connecting tube,and reservoir 150 is designed to Maintain a seal excluding fluids andair for an overall use period of two years or more. In an embodiment,the connecting tube has to be thin in order to be accommodated withinthe hinge cavity. In an embodiment, it is less than 2.0 mm in outerdiameter and less than 0.50 mm in wall thickness, in order to maintainan adequate flow of fluid. In an embodiment, it is capable of being bentby an angle of no less than 60 degrees. In an embodiment, it is capableof being bent by an angle of no less than 45 degrees without crimping.In an embodiment, it is durable to repeated flexing of the hinge.

Hinge block 250 and spring 230 are enclosed within a covered areabetween inner block 210 and outer block 240. Hinge block 250 includes agap that is shaped to allow the connecting tube to pass through hingeblock 250. Additional embodiments of the spring are described below withrespect to FIGS. 9-22. Caliper actuator assembly 100 includes wheel 130held in place by axle 280, slider 140, slider block 255, spacer block290, and compression arm 270. These parts are assembled into a templechassis subassembly and are held in place by screws 235. Rubber strip205 includes a flexible surface upon which wheel 130 may move. In anembodiment, wheel 130 may rotate. In other embodiments it may translate,and in other embodiments it may rotate and translate.

Assembly

FIGS. 3-4 illustrate a set of steps for assembling an embodiment of atemple chassis subassembly. Beginning with FIG. 3, spacer block 290 isplaced onto temple chassis 120. Next, spacer block 290 is welded ontotemple chassis 120 along edges 310 and 320. Next, hinge block 250 isplaced onto temple chassis 120. Next, hinge block 250 is welded ontotemple chassis 120 along edges 330 and 340. The temple chassissubassembly continues with FIG. 4, which illustrates a second set ofsteps for assembling an embodiment of temple chassis subassembly 400. Abacking (not shown) may be removed from tape 410 on both sides ofreservoir 150. Reservoir 150 is placed against temple chassis 120.Compression arm 270 is then placed onto spacer block 290. Compressionarm 270 is then welded onto spacer block 290.

FIG. 5 illustrates a set of steps for assembling temple subassembly 500,according to an embodiment. First, tabs 520 of temple chassissubassembly 400 are slid into rear slot 530 of temple cover 110. Next,temple chassis subassembly 400 is rotated within temple cover 110 untilit snaps into place. It is recommended that slider subassembly 295 bepositioned as far distally as possible within temple cover 110. Further,it is recommended that when snapping temple chassis subassembly 400 intotemple cover 110, tube 540 does not become pinched between hinge block250 and temple cover 110 or temple chassis subassembly 400.

FIGS. 6-7 illustrate a set of steps for assembling a frame assembly,according to an embodiment. Beginning with FIG. 6, in an embodiment, anadhesive, such as glue, is applied to the inside edge of frame 610.Next, spring 230 is placed against hinge block 250. In an embodiment,frame 610 is then pulled over lens module 200 so that upper portion 620and lower portion 630 of frame 610 are coupled with lens module 200. Anadhesive, such as glue, may be used to bond lens module 200 to frame610. One Of skill in the art will recognize that, in another embodiment,lens module 200 may be added to frame 610 after assembly of frameassembly 600 is complete. The frame assembly continues with FIG. 7,which shows a second set of steps for assembling an embodiment of frameassembly 600. In an embodiment, screws 235 are inserted into respectivescrew holes 710 in frame 610 into hinge block 250. FIG. 7 shows theframe assembled with spring 230, showing the addition of cover 720 toseal off the hinge mechanism and prevent access of water or contaminantsto connecting tube 540. The steps shown in FIGS. 6 and 7 may be repeatedfor the second temple subassembly. In an embodiment, after frameassembly 600 is assembled, adequate time is allowed for any glue oradhesive to cure.

FIG. 8 illustrates completed frame assembly 600 including temple chassis120, frame 610 and lens module 200.

Additional embodiments of hinge springs will now be described. FIG. 9illustrates an embodiment of a spring that may be used in frame assembly600. In an embodiment, spring 910 includes an end 920. Additionalembodiments of end 920 may include a canned surface. When temple arm 900rotates, end 920 rides up against a small peak 930. Force on end 920from flexing creates stored energy that releases when temple arm 900causes end 920 to move from peak 930. Temple arm 900 then acceleratesand rotates to either folded or unfolded position. A hard stop 960 maybe provided to prevent temple arm 900 from flexing too far. Duringassembly, the connecting tube (not shown) is routed through the centerof hinge 970 through gap 950.

FIG. 10 shows another embodiment of a spring that may be used in frameassembly 600. In an embodiment, spring 1010 is a sheet metal hinge thatuses a folded sheet metal arm 1020 to provide spring force. End 1030,which is closest to lens module 200 is fixed within frame 610 (notshown). End 1040 is attached to temple arm 1050, The flexure of spring1010 occurs primarily within the bend (i.e., folded sheet metal arm1020). During assembly, the connecting tube (not shown) is routedthrough the center of spring 1010 through gap 1060. Although spring 1010is referred to herein as a “sheet metal” hinge, one of skill in the artwill recognize that spring 1010 may be made of any material, even anon-metallic material, that satisfies the balance between flexibilityand rigidity needed for spring 1010 to operate.

FIG. 11 shows another embodiment of a hinge 1100. Hinge 1100 isconfigured to rotate around rotation axis A-A′ with respect to a templearm (not shown). As hinge 1100 rotates around rotation axis A-A′,cantilever tab 1110 engages with a corresponding ridge on the temple arm(not shown).

FIG. 12 shows another embodiment of a hinge 1200. Hinge 1200 isconfigured to rotate around rotation axis B-B′ with respect to a templearm (not shown). As hinge 1200 rotates around rotation axis B-B′,cantilever tab 1210 engages with a corresponding ridge on the temple arm(not shown).

FIGS. 13-16 show views of a leaf spring hinge from differentperspectives, according to an embodiment of the present invention.

FIG. 17 illustrates an exploded view Of a leaf spring hinge above abreadboard, according to an embodiment of the present invention.

FIGS. 18-21 show views of a sheet metal spring binge from differentperspectives, according to an embodiment of the present invention.

FIG. 22 illustrates an exploded view of a sheet metal spring hinge abovea breadboard, according to an embodiment of the present invention.

FIG. 23 shows several views of an assembled an embodiment of a pair ofeyeglasses from different perspectives that includes a spring inaccordance with an embodiment of the present invention.

Materials

The pieces of the various actuator assemblies described herein, forexample, but not limited to, the temple cover, temple chassis, wheel,slider, spring, screws, inner block, outer block, axle, compression arm,spacer block, etc, may be manufactured through any suitable process,such as metal injection molding (MIM), cast, machining, plasticinjection molding, and the like. The choice of materials may be furtherinformed by the requirements of, for example and without limitation,mechanical properties, temperature sensitivity, optical properties suchas dispersion, moldability properties, or any other factor apparent to aperson having ordinary skill in the art.

The fluid used in the fluid lens may be a colorless fluid; however,other embodiments include fluid that is tinted, depending on theapplication, such as if the intended application is for sunglasses. Oneexample of fluid that may be used is manufactured by Dow Corning ofMidland, Mich., under the name “diffusion pump oil,” which is alsogenerally referred to as “silicone oil.”

The fluid lens may include a rigid optical lens made of glass, plastic,or any other suitable material. Other suitable materials include, forexample and without limitation, Diethylglycol bisallyl carbonate(DEG-BAC), poly(methyl methacrylate), PMMA and a proprietary polyureacomplex, trade name TRIVEX (PPG).

The fluid lens may include a membrane made of a flexible, transparent,water impermeable material, such as, for example and without limitation,clear and elastic polyolefins, polycycloaliphatics, polyethers,polyesters, polyimides and polyurethanes, for example, polyvinylidenechloride films, including commercially available films, such as thosemanufactured as MYLAR or SARAN. Other polymers suitable for use asmembrane materials include, for example and without limitation,polysulfones, polyurethanes, polythiourethanes, polyethyleneterephthalate, polymers of cyclooiefins and aliphatic or alicyclicpolyethers.

The connecting tube may be made of one or more materials such as TYGON(polyvinyl chloride), PVDF (Polyvinyledene fluoride), and naturalrubber. For example, PVDF (such as heat-shrunk flexible PVDF) may besuitable based on its durability, permeability, and resistance tocrimping. In addition

The temple cover may be any suitable shape, and may be made of plastic,metal, or any other suitable material. In an embodiment, the templecover is made of a lightweight material such as, for example and withoutlimitation, high impact resistant plastics material, aluminum, titanium,or the like. In an embodiment, the temple cover may be made entirely orpartly of a transparent material.

The reservoir may be made of Polyvinyiedene Difluoride, such asHeat-shrink VITON®, supplied by DuPont Performance Elastomers LLC ofWilmington, Del., DERAY-KYF 190 manufactured by DSG-CANUSA ofMeckenheim, Germany (flexible), RW-175 manufactured by Tyco ElectronicsCorp. of Berwyn, Pa. (formerly Raychem Corp.) (semirigid), or any othersuitable material.

The screws used in the frame assembly may include, for example andwithout limitation, Visottica 07V120037017 shoulder screws produced byVisottica Industrie S.P.A. of Susegana, Italy. Other suitable types ofscrews or other attachment means, such as rivets, may be used.

Although various embodiments of the present invention have beendescribed above, it should be understood that they have been presentedby way of example only, and not limitation. It will be apparent topersons skilled in the relevant art that various changes in form anddetail can be made therein without departing from the spirit and scopeof the invention. Thus, the breadth and scope of the present inventionshould not be limited by any of the above-described exemplaryembodiments, but should be defined only in accordance with the followingclaims and their equivalents.

Further, the purpose of the foregoing Abstract is to enable the U.S.Patent and Trademark Office and the public generally, and especially thescientists, engineers and practitioners in the art who are not familiarwith patent or legal terms or phraseology, to determine quickly from acursory inspection the nature and essence of the technical disclosure ofthe application. The Abstract is not intended to be limiting as to thescope of the present invention in any way.

1. A hinge for a fluid-filled lens assembly, the hinge comprising: afolded sheet arm comprising: a bend portion; a first end configured toconnect to a temple arm of the fluid-filled lens assembly; and a secondend configured to connect to a frame of the fluid-filled lens assembly,wherein the folded sheet arm is configured to have a flexure to occurwithin the bend portion; wherein the folded sheet arm is configured toform a gap to be shaped to allow a tube for passing fluid to pass fromthe first end to the second end of the folded sheet arm, wherein the gaphas a sufficient size that allows the tube to bend without kinking whenthe temple arm is rotated between an open position in which the templearm is substantially perpendicular to the frame and a closed position inwhich the temple arm is substantially parallel to the frame, wherein thefolded sheet arm is configured to engage the temple arm when the templearm is rotated in a first direction to create spring energy in the hingethat resists further rotation of the temple arm, and wherein the foldedsheet arm is configured to release the spring energy in the hinge toaccelerate the temple arm when the temple arm is rotated in a seconddirection.
 2. The hinge of claim 1, wherein the fluid-filled lensassembly is an eyeglass assembly.
 3. The hinge of claim 2, wherein theeyeglass assembly includes a temple arm, and wherein the hinge isdisposed at least partially within the temple arm.
 4. A hinge for afluid-filled lens assembly, the hinge comprising: a folded sheet armcomprising: a bend portion; a first end configured to connect to atemple arm of the fluid-filled lens assembly; and a second endconfigured to connect to a frame of the fluid-filled lens assembly,wherein the folded sheet arm is configured to have a flexure to occurwithin the bend portion; wherein the folded sheet arm is configured toform a gap to be shaped to allow a tube for passing fluid to pass fromthe first end to the second end of the folded sheet arm, and wherein thefirst and second ends of the folded sheet arm are configured to flexaround a rotation axis of the hinge between an open position in whichthe temple arm is substantially perpendicular to the frame and a closedposition in which the temple arm is substantially parallel to the frame.5. The hinge of claim 4, wherein the bend portion of the folded sheetarm is U-shaped configured to bend around the rotation axis of thehinge.
 6. The hinge of claim 4, wherein the gap has a sufficient sizethat allows the tube to bend without kinking when the temple arm isrotated between an open position in which the temple arm issubstantially perpendicular to the frame and a closed position in whichthe temple arm is substantially parallel to the frame.
 7. The hinge ofclaim 4, wherein the fluid-filled lens assembly is an eyeglass assembly.8. The hinge of claim 7, wherein the eyeglass assembly includes a templearm, and wherein the hinge is disposed at least partially within thetemple arm.
 9. A fluid-filled lens assembly comprising: a temple arm; areservoir disposed within the housing; a fluid-filled lens disposedwithin the frame; a tube for passing fluid connecting the reservoir tothe fluid-filled lens; and a hinge including a folded sheet arm, thefolded sheet arm comprising: a bend portion; a first end configured toconnect to a temple arm of the fluid-filled lens assembly; and a secondend configured to connect to a frame of the fluid-filled lens assembly,wherein the folded sheet arm is configured to have a flexure to occurwithin the bend portion; wherein the folded sheet arm is configured toform a gap to be shaped to allow a tube for passing fluid to pass fromthe first end to the second end of the folded sheet arm, wherein the gaphas a sufficient size that allows the tube to bend without kinking whenthe temple arm is rotated between an open position in which the templearm is substantially perpendicular to the frame and a closed position inwhich the temple arm is substantially parallel to the frame, and whereinthe first and second ends of the folded sheet arm are configured to flexaround a rotation axis of the hinge between an open position in whichthe temple arm is substantially perpendicular to the frame and a closedposition in which the temple arm is substantially parallel to the frame.10. The hinge of claim 9, wherein the bend portion of the folded sheetarm is U-shaped configured to bend around the rotation axis of thehinge.
 11. The fluid-filled lens assembly of claim 9, wherein thefluid-filled lens assembly is an eyeglass assembly.
 12. The hinge ofclaim 11, wherein the eyeglass assembly includes a temple arm, andwherein the hinge is disposed at least partially within the temple arm.